A wireless network provides a flexible data communication system that can either replace or extend a wired network. Using radio frequency (RF) technology, wireless networks transmit and receive data over the air through walls, ceilings, and cement structures without wired cabling. For example, a wireless local area network (WLAN) provides all the features and benefits of traditional LAN technology, such as Ethernet and Token Ring, but without the limitations of being tethered together by a cable. A WLAN can provide greater freedom and increased flexibility than traditional wired networks.
Currently, a wireless network operating in accordance with the Institute of Electrical and Electronic Engineers (IEEE) 802.11 Standard (e.g., IEEE Std. 802.11 a/b/e/g/n/s) may be configured in one of two operating modes: infrastructure mode; and ad hoc mode. As of today, most installed wireless networks are configured and operate in infrastructure mode—where one or more access points (APs) are configured as interfaces for a wired distribution network (e.g., Ethernet). In infrastructure mode, mobile devices with wireless connectivity (e.g., laptop computer with a radio network interface card “NIC”) are able to establish communications with the AP; the users of these devices access content within servers connected to the wired network.
As an optional feature, however, the IEEE 802.11 Standard specifies “ad hoc” mode, which allows the radio NIC within each wireless device to operate in an independent basic service set (IBSS) network configuration. In ad hoc mode, the wireless devices perform peer-to-peer communications with each other instead of utilizing the AP for supporting such wireless communications. The ad hoc mode also allows users to spontaneously form a wireless LAN. For example, a group of employees (with laptops implemented with IEEE 802.11 wireless chipsets) may gather at a coffee house and form a small WLAN by switching their NICs to ad hoc mode. As a result, the employees could share presentation charts and spreadsheets without the need for cabling.
One type of ad hoc network is referred to as a mesh network, which allows for continuous connections and reconfiguration around broken or blocked paths by “topping” from device to device until a destination is reached. Mesh networks differ from other networks; in a mesh network, the devices can all connect to each other via multiple hops without an infrastructure (e.g., an AP), and these devices can be mobile or stationary. Related to mesh networks, mobile ad-hoc networks (MANETs) are self-configuring networks of mobile routers, where the routers are free to relocate.
One of the primary advantages of mesh networks (and MANETs) is their ability to extend the range of the wireless network. For example, a user on one side of the building can send a packet destined to another user on the far side of the facility, well beyond the point-to-point range of IEEE 802.11-compliant AP, by having the radio signal hop from one mobile device to mobile device until the radio signal reaches a targeted destination. This can extend the range of the WLAN from hundreds of feet to miles, depending on the concentration of wireless users.
With recent technology advances in integrated circuits, and breakthroughs in multiple input and multiple output (MEMO) systems, wireless digital communications entered a new era of faster speed wireless networking applications. Mobile devices such as smart phones, music/movie players, personal digital assistants, gaming devices and the like, are creating a demand for new wireless communication and networking technologies to allow seamless connection of wireless mobile devices.